title: Dynamic lattice distortions in Sr2RuO4: microscopic studies by perturbed angular correlation spectroscopy and ab initio calculations.
abstract: Applying time differential perturbed angular correlation (TDPAC) spectroscopy and ab initio calculations, we have investigated possible lattice instabilities in Sr(2)RuO(4) by studying the electric quadrupole interaction of a (111)Cd probe at the Ru site. We find evidence for a dynamic lattice distortion, revealed from the observations of: (i) a rapidly fluctuating electric-field gradient (EFG) tensor showing non-Arrhenius relaxation, (ii) an anomalous temperature dependence of the quadrupole interaction frequency, and (iii) a monotonic increase of the EFG asymmetry (η) below 300 K. We argue that the observed dynamic lattice distortion is caused by strong spin fluctuations associated with the inherent magnetic instability in Sr(2)RuO(4).
authors.affiliation: Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai-400005, India.
authors.forename: S N
authors.initials: SN
authors.lastname: Mishra
authors.forename: M
authors.initials: M
authors.lastname: Rots
authors.forename: S
authors.initials: S
authors.lastname: Cottenier